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Chinese Chemical Letters 2017年第2期28卷 446-452页

作者： Afshin yazdani-Elah-Abadi Malek-Taher Maghsoodlou Razieh Mohebat Reza Heydari Department of Chemistry Faculty of Science University of Sistan and Baluchestan P.O. Box 98135-674 Zahedan Iran Department of Chemistry Yazd Branch Islamic Azad University Yazd Iran

A green,convenient,high yielding and one-pot procedure for the synthesis of novel spiro[benzo[α]pyrano[2,3-c]phenazine]derivatives by domino multi-component condensation reaction between 2-hydroxynaphthalene-l,4-dione,benzene-l,2-diamines,ninhydrine,and malononitrile in the presence of a catalytic amount of 1,3-dimethyl-7H-purine-2,6-dione（theophylline） as an expedient,eco-friendly and reusable solid base catalyst under thermal,microwave irradiation and solvent-free *** procedure has also been applied successfully for the synthesis of benzo[α]pyrano[2,3-c]phenazines.

关键词： Multi-component domino reactions(MDRs) Green chemistry Theophylline Spiro[benzo[α]pyrano[2 3-c]phenazine] Benzo[α]pyrano[2 3-c]phenazine

A facile method for fabrication of nano-structured Ni-Al_2O_3 graded coatings: Structural characterization

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Transactions of Nonferrous Metals Society of China 2018年第1期28卷 77-87页

作者： Arash yazdani Taghi ISFAHANI Materials Science and Engineering Program University of California Department of Mechanical and Aerospace Engineering University of California Metallurgy & Materials Engineering Department Golpayegan University of Technology

Powder charges of micron-size Ni and Al2O3were utilized to deposit nano-structured Ni-Al2O3composite coatings on analuminum plate fixed at the top end of a milling vial using a planetary ball *** coatings were fabricated using powdermixtures with a wide range of Ni/Al2O3mass ratio varying from1:1to plain ***,SEM and TEM techniques were employed tostudy the structural characteristics of the *** was found that the composition of the starting mixture strongly affects the Al2O3content and the microstructure of the final *** containing higher contents of Al2O3yield higher volume fractions of theAl2O3particles in the *** Ni-Al2O3composite coatings with about50%of Al2O3particles were successfully deposited,well-compacted and free of cracks and/or voids coatings included less than20%(volume fraction)of Al2O3particles which weredeposited from powder mixtures with Ni/Al2O3mass ratios of4:1or ***,mechanical and metallurgical bondings arethe main mechanisms of the adhesion of the coating to the Al ***,functionally graded composite coatings withnoticeable compaction and integrity were produced by deposition of two separate layers under identical coating conditions.

关键词： metal matrix composite Ni-Al2O3 graded coating structural characterization

DABCO-catalyzed multi-component domino reactions for green and efficient synthesis of novel 3-oxo-3H-benzo[a]pyrano[2,3-c]phenazine-1-carboxylate and 3-(5-hydroxybenzo[a]phenazin-6-yl)acrylate derivatives in water

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Chinese Chemical Letters 2017年第5期28卷 943-948页

作者： Razieh Mohebat Afshin yazdani-Elah-Abadi Malek-Taher Maghsoodlou Nourallah Hazeri Young Researchers and Elite Club Yazd BranchIslamic Azad UniversityYazdIran Department of Chemistry Faculty of ScienceUniversity of Sistan and BaluchestanP.O.Box 98135-674ZahedanIran

An efficient,convenient and environmentally benign procedure for the synthesis of novel 3-oxo-3Hbenzo[a]pyrano[2.3-c]phenazine-l-carboxylate and 3-（5-hydroxybenzo[a]phenazin-6-yl） acrylate derivatives has been developed by domino three-component condensation reaction between 2-hydroxynaphthalene-1,4-dione,benzene-1,2-diamines and acetylenic esters in the presence of a catalytic amount of DABCO as an expedient,eco-friendly and reusable base catalyst in *** green process produces biologically and pharmacologically significant heterocycles in a one-pot single operation and offers considerable advantages such as：operational simplicity,short reaction time,high yields,reusability of catalyst,absence of any tedious workup or purification and avoids hazardous reagents/solvents.

关键词： Multi-component domino reactions(MDRs) DABCO Acetylenic esters Benzo[a]phenazin derivatives Green chemistry

Dry sliding wear of Ni alloyed austempered ductile iron

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China Foundry 2016年第5期13卷 361-367页

作者： E.Akbarzadeh Chiniforush M.A.Rahimi S.yazdani Faculty of Materials Engineering Sahand University of Technology

Measurements of dry sliding wear are presented for ductile irons with composition Fe-3.56C-2.67Si- 0.25Mo-0.5Cu and Ni contents of 0.8 and 1.5 in wt.% with applied loads of 50, 100 and 150 N for austempering temperatures of 270, 320, and 370 ℃ after austenitizing at 870 ℃ for 120 min. The mechanical property measurements show that the grades of the ASTM 897M： 1990 Standard can be satisfied for the selected austempering conditions. The results show that wear resistance is independent of austempedng temperature with an applied load of 50 N, but there is a strong dependence at higher austempering temperatures with applied loads of 100 and 150 N. Observations indicate that wear is due to subsurface fatigue with cracks nucleated at deformed graphite nodules.

关键词： austempered ductile iron wear austenite ausferrite nickel

Effect of nodule count and austempering heat treatment on segregation behavior of alloying elements in ductile cast iron

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China Foundry 2016年第3期13卷 217-222页

作者： E.Akbarzadeh Chiniforush N.Iranipour S.yazdani Faculty of Materials Engineering Sahand University of Technology Deakin University Institute for Technology Research and Innovation

The equilibrium partition ratio, k, has been measured for Mn, Mo, Si, Ni and Cu in a ductile iron with composition(wt.%): 3.45 C, 0.25 Mn, 0.25 Mo, 2.45 Si, 0.5Ni and 0.5Cu with different nodule counts obtained from different section sizes of13, 25, 75 mm in the as cast, austenitized(at 870 °C for times 1, 4 and 6 hours) and austempered(at 375 °C for times 1 to 1,440 min) samples. Results show that Mn and Mo segregate positively at cell boundaries, but Si, Ni and Cu concentrate in an inverse manner in the vicinity ofgraphite nodules and there is a depletion ofthese elements at cell boundaries. Segregation curves for Ni and Cu are more smooth than for Si. Carbide formation has been observed at cell boundaries. Based on the results, the partition ratios for all elements decrease with increasing the nodule count. More carbide with coarser morphology has been observed in the microstructure with a lower nodule count. Austenitization for a longer time can decrease partition ratio, but cannot eliminate it entirely. Increasing the austenitization temperature has the same effect. Austenitizing parameters have no significant effect on carbides volume fraction. The kinetics ofaustempering is faster in higher nodule counts and subsequently better mechanical properties including higher ductility, strength and toughness have been observed for all austempering conditions studied.

关键词： segregation ductile iron austenitization austempering

Carotenoid Metabolism in Plants： The Role ol Plastids

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Molecular Plant 2018年第1期11卷 58-74页

作者： Tianhu Sun Hui Yuan Hongbo Cao Mohammad yazdani Yaakov Tadmor Li Li Robert W. Holley Center for Agriculture and Health USDA-ARS Cornell University Ithaca NY 14853 USA plant Breeding and Genetics Section School of Integrative Plant Science Cornell University Ithaca NY 14853 USA College of Horticulture Hebei Agricultural University Baoding Hebei 071001 China Plant Science Institute Israeli Agricultural Research Organization Newe Yaar Research Center P.O. Box 1021 Ramat Yishai 30095 Israel

Carotenoids are indispensable to plants and critical in human diets. Plastids are the organelles for carotenoid biosynthesis and storage in plant cells. They exist in various types, which include proplastids, etioplasts, chloroplasts, amyloplasts, and chromoplasts. These plastids have dramatic differences in their capacity to synthesize and sequester carotenoids. Clearly, plastids play a central role in governing carotenogenic activity, carotenoid stability, and pigment diversity. Understanding of carotenoid metabolism and accumulation in various plastids expands our view on the multifaceted regulation of carotenogenesis and facilitates our efforts toward developing nutrient-enriched food crops. In this review, we provide a comprehensive overview of the impact of various types of plastids on carotenoid biosynthesis and accumulation, and discuss recent advances in our understanding of the regulatory control of carotenogenesis and metabolic engineering of carotenoids in light of plastid types in plants.

关键词： carotenoid plastid regulation metabolism metabolic engineering

An Investigation on Rotating Bending Fatigue Behavior of Nanostructured Low-Temperature Bainitic Steel

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Acta Metallurgica Sinica(English Letters) 2014年第2期27卷 233-238页

作者： B.R.Shendy M.N.Yoozbashi B.Avishan S.yazdani Faculty of Materials Engineering Sahand University of Technology University of Applied Science and Technology Faculty of Engineering Azarbaijan Shahid Madani University

The aim of this work is to investigate the fatigue behavior of a new class of nanostructured, low-temperature bainitic steels, where rotating bending fatigue tests were conducted on samples isothermally transformed at 300, 250, and 200 ℃, after which, fracture surfaces were examined using scanning electron microscopy. Results showed that, fatigue limits of about 820, 945, and 1,005 MPa were achieved for the samples transformed at each transformation temperature, respectively. Moreover, according to the SEM micrographs, secondary crack initiation was observed in the high carbon retained austenite blocks for samples transformed at 300 ℃ and at the interface of blocky austenite-bainitic ferrite for samples transformed at 250 and 200 ℃.

关键词： Fatigue Bainitic ferrite Retained austenite Fractography

A new model to predict roadheader performance using rock mass properties

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Journal of Coal Science & Engineering(China) 2013年第1期19卷 51-56页

作者： yazdani-Chamzini ABDOLREZA SIAMAK Haji Yakhchali Young Researchers Club South Tehran Branch Islamic Azad University Tehran 14115/344 Iran Department of Industrial Engineering College of Engineering University of Tehran Tehran 11365/7117 Iran

Prediction of roadheader performance plays a significant role in the plan of tunnel construction, which is influenced by different key parameters, including rock strength, discontinuity in rock mass, type and specifications of roadheader machine, and brittleness. The main aim of this study is to build a robust empirical equation based on rock mass properties for the roadheader performance prediction. For achieving the aim, a dataset composed of roadheader performance rate and rock properties is established using the dataset compiled from an underground coal mine located in a remote rugged desert environment some 85 km south of Tabas City in mid east Iran. By using gathered data, the statistical analyses are conducted between rock mass properties and roadheader performance to find whether there is a significant relationship between input variables and roadheader performance. The results show that rock mass properties have a considerable impact on the rate of the roadheader performance. It is demonstrated that the proposed model can accurately predict the roadheader performance as a function of rock mass properties.

关键词： roadheader performance Tabas Coal Mine rock mass property alpha angle prediction

Comparative analysis of cast-in-place post-tensioned and steel-concrete composite bridge bent caps

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Journal of Modern Transportation 2017年第3期25卷 194-204页

作者： Nur yazdani Francisco D.B.Ruiz Department of Civil Engineering University of Texas at Arlington Structural Engineer Ferrovial-Agroman

The complexity of the IH-635 Managed Lanes Project, located in Dallas County, Texas, posed several technical and constructive challenges, leading to the adoption of solutions different from the traditional. Two alternative solutions for the pier cap on one of the bridge crossings over IH-35E in the IH-635 project were analyzed in this case study, a cast-in-place post-tensioned concrete cap and an innovative prefabricated steel-concrete com- posite cap. The approach was to use an estimation of direct costs for material and labor and consideration of con- struction time schedules. A supplementary numerical modeling confirmed that both alternatives behave elasti- cally under imposed loads. The direct cost of material and labor for the two alternatives were close. However, the composite alternative required 13 days less construction time, resulting in substantial cost savings from traffic closing in the very busy traffic corridor. Traffic closing costs were substantially higher than the direct costs, especially for the post-tensioned cap. The quantification of the benefits allows more confidence in the utilization of the composites caps, leading to faster completion of bridge projects and substantial economic savings.

关键词： Bridge pier cap Bridge bent - Post-tensionedstructure Steel-concrete cap Cost estimation Construction schedule Traffic closing cost

Provincial clustering of malaria in Iran between 2005 and 2014

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Asian Pacific Journal of Tropical Medicine 2020年第4期13卷 162-168页

作者： Vahid Moqarabzadeh Ahmad Ali Enayati Ahmad Raeisi Fatemeh Nikpour Jamshid yazdani Charati Department of Biostatistics&Epidemiology School of HealthMazandaran University of Medical SciencesSariIran Medical Entomology Mazandaran University of Medical SciencesSariIran Department of Medical Entomology and Vector Control School of Public HealthTehran University of Medical SciencesTehranIran Department of Environmental Chemical Pollutants and Pesticides Institute for Environmental ResearchTehran University of Medical SciencesTehranIran Department of Biostatistics Health Sciences Research CenterAddiction InstituteMazandaran University of Medical SciencesSariIran

Objective: To reveal the provincial clustering of malaria in Iran between 2005 and 2014 based on the epidemiologic factors and the climatic indicators affecting the disease. Methods: This was a descriptive-analytical study using malaria and meteorological data from the Malaria Elimination Programme of the Ministry of Health and Medical Education and National Meteorological Organization. After standardization, the aggregate data was used to produce 10-year means for each province. The data analysis included grouping the provinces with respect to factors using hierarchical clustering method and Kruskal-Wallis test to examine the difference between clusters using SPSS ver.23. Results: The hierarchical clustering stratified the provinces' in 5 clusters. Kruskal-Wallis H test revealed a significant difference in the incidence rate per 100000 population (P=0.001), male gender (P=0.001), Iranian nationality (P=0.001), Afghan nationality (P=0.003), Pakistani nationality (P=0.001), urban residence (P=0.006), rural residence (P=0.004), autochthonous cases (P=0.007), average minimum temperature (P=0.001), average maximum temperature (P=0.007), average relative humidity (P=0.011), average pressure level (P=0.038), prevailing wind direction (P=0.023), average wind speed (P=0.031) and average precipitation sum (P=0.002) among the clusters. Conclusions: The results of this study and stratification of the provinces could help health policy makers to better manage malaria by allocating resources accordingly.

关键词： Malaria Cluster analysis Iran